UML Activity Diagram :loop on decision node

Question

I am learning UML and I would like to know if it is possible to loop on the decision node. Because in my cockburn I have :

3-Enter with ticket
3a1-Enter with card 3a2-Failure: return to 1

If it is possible, how can I do it with Visual Paradigm? Thanks!

Answer 1

You can't do that in UML. A decision node is just for evaluation of a condition previously set in an action.

From your scenario it's not obvious how you want to establish a loop anyway. I would guess that the case "none selected" needs to be modeled. Just make your action above not deliver anything else but the ticket/card conditions.

Answer 2

I assume you're asking if it's possible to loop from a decision back to itself. Doing so would create an infinite loop. The reason is that the guard condition would never have a chance to change, so the token would cycle forever.